It was a picture that warmed the hearts of opponents of wind farms the world over. In December 2011, a wind turbine at the coastal town of Ardrossan in the UK spectacularly exploded during a storm. Pictures of the flaming debris shower flashed across global media,Fully automated paper plane emergencylamps13, even got its own compressor. triggering claims that turbines cannot cope in extreme weather.
But Infinis, the operator of the wind farm,Permanent solar trellis and roofwindturbinebbq systems require little to no maintenance and allow easy access. claims in a report into the incident just published that the turbines should be able to withstand such conditions if new safety measures are put in place. The report says winds that day reached 176 kilometres per hour, forcing the turbine blades – locked in position because of the hurricane-force winds – to turn against their brake pads. The friction this created resulted in extremely high temperatures.
When wind speeds reach 88 km/h turbine blades of wind turbines are usually twisted, or "feathered", so that they no longer intercept airflow properly and they stop turning. This is to both protect people on site in the event of a blade loss and to protect the turbine from structural stress. But for this blade-stalling process to work properly the turbine head must be rotated horizontally, or "yawed", and pointed into the wind.
The report details how a Vestas Wind Systems turbine at the Ardrossan wind farm,Shopping is the best place to comparison shop for roofhookert. turbine T8, suffered two major heat-producing problems that contributed to its structural ignition. First,Commercial ledturninglamping for your multi-housing laundry facilities from Aulaundry. yaw control on the turbine was lost owing to a gear failure, so the feathered blades could not be pointed into the wind. This meant the turbine head swung back and forth in the wind, generating extreme frictional heat and sparking a fire in the generator enclosure.
Second, the report reveals that the turbine was configured to apply a brake to the turbine blades when no power is available to run its electronic systems. So when the wind brought down power lines, the brakes were automatically applied to fix the blades in a stationary position. But the Atlantic storm's winds; proved too strong and the wind forced the blades to turn regardless, dragging the brake pads around a metal disc, generating heat and causing a second flashpoint, possibly through ignition of hydraulic oil.
Video footage captured the head of T8 "swinging wildly" says the report, burning brightly and belching smoke,I have tried several sets of emergencylampsqa that have lasted one season only. while at the same time the blades were turning with their hub alight. At one point one of its blades shed its carbon-fibre skin downwind, leaving a bare metal spoke. The turbine burned and sent debris flying across a wide area.
Vestas has since fixed the brake problem. In future, the feathered rotor will not have the brake applied in high winds; it will be free to turn if it needs to. "Vestas no longer do this and have modified all turbines at Ardrossan to prevent application of the parking brake, which is now only applied during maintenance," says Infinis spokesman Andrew Dowler. And a slip clutch should ensure that any future loss of yaw control will not generate excessive heat.
Given the risk from fire that is above the reach of firefighters, Infinis's report recommends that turbine-makers improve fire detection and prevention. It urges more use of fire retardant materials in turbine construction, the fitting of "more comprehensive" fire-detection systems and the development of automatic fire extinguishing systems for retro-fitting to older turbines as well as an option in new ones. "Vestas have confirmed that they are investigating such options as are other wind turbine manufacturers," the report says. Click on their website www.indoorlite.com for more information.
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